Thermoplastic liquid-crystalline polymer (which is abbreviated as “LCP” hereinafter) has good properties including heat resistance, mechanical properties such as rigidity, chemical resistance and dimensional accuracy. Due to those properties, LCPs are used not only for manufacturing molded articles but also for a variety of products including fibers and films.
In the information and telecommunication fields, very thin parts are sometimes required. Particularly, personal computers and mobile phones employ highly integrated devices and the art wishes to use downsized, thinner and smaller parts for them. Because of those excellent properties of the LCPs, consumption of LCPs has been increasing in these days.
For mounting electronic components such as connectors, environmentally conscious lead free solders are preferably used in these days. The reflow temperature of the lead free solders are relatively high and the higher temperature sometimes cause blister formation on the surface of the component made of LCP.
In addition, the higher reflow temperatures may also cause warpage of the component. In order to avoid warpage, fillers such as talc have been added to a LCP composition.
Talc comprises small amount of water and the LCP compositions comprising talc have the problem of blister formation because of the water introduced simultaneously with talc.
In order to avoid blister formation on the surface of the molded LCP articles, various strategies have been proposed. For example, adding additives such as silicone gum, phosphoric compound or boric compound to the LCP composition (Japanese Patent Application Laid Open Nos. 02-075653, 06-032880, 10-036641, 10-158482, 11-140283, 11-199761, 2003-096279 and 2004-196886, the references are herein incorporated by reference); controlling the screw compression ratio upon injection molding the LCP (Japanese Patent Application Laid Open No. 11-048278); and adjusting the screw of a kneader for kneading the LCP and the inorganic fillers so that the meshing ratio of the screw is in a certain range (Japanese Patent Application Laid Open No. 2003-211443).
There are various LCP compositions comprising a LCP and a variety of fillers, reinforcements, and additives including the composition comprising a LCP and a low-temperature softening inorganic glass filler (Japanese Patent Application Laid Open Nos. 09-022969, 09-019938, 07-309634).
The LCP compositions comprising low-temperature softening inorganic glass fillers disclosed in the prior art references comprise a relatively large amount of the low temperature softening inorganic glass filler and therefore, the LCP composition cannot be used for manufacturing devices or components used in the field where precise size and shape are required. A LCP composition comprising a LCP and only a small amount of the low temperature softening inorganic glass filler has not been known.